High-potential insulator.



L. STEINBERGER.

HIGH POTENTIAL INSULATOR.

APPLICATION FILED AUG.2I. m2.

1 ,206, 1 60. Patented Nov. 28, 1916.

WITNESSES 6' "IVE/ TOR m: mmms Psrwcs ca. Puuwuma. WASII/NDTUN. 0. c

LOUIS STEINBERGER, OF NEW YORK, N. Y.

HIGH-POTENTIAL INSULATOR.

I Specification of Letters Patent.

Application filed August 21, 1912. Serial No. 716,157.

To all whom it may concern:

Be it known that I, LOUIS Srnmnnncnn, residing at Brooklyn, in the county of Kings, city and State of New York,'-have invented certain new and useful Improvenients in High Potential Insulators, of which the following is a specification.

This invention relates to a high potential insulator, particularly of the pm type, designed to possess high insulating value compared with the amount of material and weight employed, and having a maximum of mechanical strength.

Among the more important objects of the invention may be enumerated the following:

I. To improve the construction of high voltage pin type insulators and of their means of attachment.

II. To provide against likelihood ,of puncture incident to an abnormal electric discharge from line to ground, such for instance as might result from lightning striking the line,'or from other causes.

III. To provide apin-type insulator comprising a head ,part and a stem part, both of lnsulating material, and to form the stem part separately from the head part and of a relatively tougher material than the head part, to mold the head part rigidly about the upper end of the stem part ,to form a substantially integral structure, and to adapt the stem part .to be attached by its lower end to a suitable support.

IV. To provide a pin-type insulator, having asubstantially cylindrical solid columnlike body portion or stem of insulating material, and to provide a reinforcing member encircling the'lower portion of the body serving as attaching means for attaching the body to a support, and to provide a separately formed head part supported upon the upper end of thebody serving as means for attaching a conductor, and to provide a part formed upon the head extending downwardly around and protecting the body, the reinforcing member, and particularly the joint'between the body and'the reinforcing member.

V. To provide a pin-typeinsulato'r comprising independently formedbody and conductor attaching parts, both of insulating material, the conductor attaching part, or head, being formed with enlarged protective hoods or skirts and being relatively massive, and being of fictile material, to form the body part of a relatively small,

elongated, solid, column-like, cylindrical member of a relatively tougher insulating material having its upper end portion molded rigidly within the fictile material of the head'part, and to provide formations upon the embedded upper end of the body to be engaged by said fictile material of the head to positively prevent relative rotation and disengagement of said parts, and to form the lowerend portionof the body part for detachable threaded engagement with a suitable support.

Other objects and aims of the invention, more or less specific than those referred to above, will be in part obvious and in part pointed out in the course of the following description of the elements, combinations, arrangements of parts and applications of principles, constituting the invention; .and the scope ofprotection contemplated will be indicated in the appended claim.

In the accompanying drawing I have illustrated a side elevational view, partly in section, of one embodiment of an insulator constructed in accordance with the provisions of this invention.

Since, insulators of this class, adapted for sustaining very high voltages, are of necessity, quite massive, it follows that their means of attachment to their support must be substantial. It is, of course, desirable to bring about this result without decreasing the insulating properties of the insulator, and also without adding materially to the weight of the structure. In this respect particularly the present application is intended as an improvement over the structure and the attaching means disclosed in my copending applications, Serial Nos. 711,465 and 714,37 6. In the former of these -pending applications I have illustrated a pin type insulator having a head and a solid elongated cylindrical body portion or stem, depending therefrom, all formed integral of insulating material having the same tensile strength throughout, and the body portion being provided, at its lower end, with means for attaching to a support somewhat similar to that disclosed herein. This integral structure requires that the body be relatively heavy in order to secure the necessary mechanical strength. In the latter of these co-pending applications I have disclosed similar integrally formed head and body portions. The body, in this instance, is relatively smaller and lighter, but is rein- Patented Nov. 28, 1916. i

forced by a metallic rod extending longitudinally thereof for reinforcing the same against fracture. This rod, however, provides a conductive path which tends to induce puncture through the material of the insulator, especially if the rod be extended throughout the length of the body and into too close proximity to the supported conductor.

In the present application I have disclosed an arrangement of parts such as will afiord ample resistance to fracture without the necessity for the insertion of metallic reinforcing members, or for the addition of bulk for adding strength to the elongated body in supporting the upper portion of the insulator. This means includes forming the whole of the elongated body portion as an independent part of an insulating material having a considerable greater mechanical strength than the protective and conductorsupporting part of the insulator, and of molding the two parts rigidly together to form a substantially integral structure.

Referring to the drawing for describing the structure of the present application in detail, the numeral 1 indicates a substantially cylindrical, column-like, stem or body portion of a pin type insulator, formed at its upper end with a transverse groove 2 for a purpose presently apparent. An annular groove 3 is preferably formed in the material of the body portion 1, adjacent its upper end, also for a purpose presently apparent. The lower end of the body portion 1 extends into a metallic sleeve 4: which projects upwardly about the body of the insulator from an enlarged extension 5, of a bolt 6, which bolt is extended through the cross arm or other support 7 for the insulator. One or more nuts 8 are threaded upon the lower end of the bolt 6 for drawing the enlarged extension 5 thereof against the upper surface of the cross arm 7.

The lower end of the body portion 1 may be fixed within the sleeve 4: in any suitable manner, but is preferably formed with external coarse threads 9 mating with threads 10 formed interiorly of the encircling portion of the sleeve 1, whereby it may be readily detached from said sleeve, when desired.

The protective part of the insulator may be relatively massive, as shown, comprising what might be termed a secondary body portion 11 molded rigidly about the upper portion of the body 1, the transverse groove 2 and the annular groove 3 being engaged by the material of the secondary body portion, when the same is molded thereabout, so as to effectually prevent disengagement of the protective part from the body and to prevent relative rotation.

The secondary body 11 shown is prefer- I ably cylindrical and depends for a considerable distance about the body 1, and for approximately an equal distance above the upper end thereof, the upper end of the secondary body being formed with a transversely extending groove 12 across its upper surface, adapted to receive the supported conductor 13, and with an annular groove let adapted to receive a tie wire 15 for binding the conductor 13 within the transverse groove 12, as will be understood in the art.

The lower end of the secondary body portion 1a is formed with an annular, downwardly and outwardly flaring, flange, or skirt 16, inclosing and protecting the upper end of the metallic sleeve at, and the intermediate portion of the body 1. Adjacent the upper end of the secondary body 11 shown is provided an annular projecting main or protective hood 17, preferably having its upper surface flaring outwardly and downwardly from just beneath the annular groove 14, and for a considerable distance radially beyond the outermost portions of the skirt 16, for effectually protecting parts therebeneath, including the skirt 16, and an intermediate annular skirt 18 projecting from the angle formed by the under-surface of the hood 17 and the outer surface of the cylindrical portion of the secondary body 11. The under surface of each of the hoods or flange portions 16, 17 and 18 inclines upwardly toward the body of the insulator, so as to effectually prevent travel of moisture therealong toward said body.

The protective part is molded of an insulating material, preferably electrose, which is compounded so as to be capable of resisting, without danger of puncture, very high voltages, while the body 1 is made of an insulating material as hard wood especially adapted for resisting mechanical stresses, thus, the insulating protective part, directly supporting the conductor 13, and the body 1, rigidly connected to the cross arm, and to-the protective part, forms a structure having all necessary mechanical strength, and at the same time being capable of resisting the passage of very heavy currents from the conductor to the insulator support. No metal part extends through any portion of the insulating material toward the supported conductor, such as might tend to induce puncture through the insulator from the conductor to said metallic part.

The protective part, being molded directly upon the material of the body part, avoids all possibility of interstices such as might retain a quantity of moisture or dust which would afford a conducting path along the joint between the parts and tend to promote puncture of the protective part. The upper end portions of the body 1 are rounded so as to be devoid of sharp corners such as might tend to induce fracture of the enveloping fictile material and the presence of which would also operate to project a concentrating point toward the supported conductor such as might tend to promote puncture.

In order to more efficiently support the head upon the body, the body may be formed with a more or less prominent annular shoulder in a position to engage against the under surface portion of the head, as clearly illustrated in the drawings.

The flange 16, flaring outwardly across and covering the joint between the body 1 and the sleeve 4 serves to protect and positively prevent the entrance of moisture into the interstices at the threads between the body and the sleeve 4.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the language used in the following claim is intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention, which as a matter of language, might be saidto fall therebetween.

Having thus described my invention what I claim as new and desire to secure by Letters Patent, is:

A pin type insulator comprising a head part and a cylindrical stem depending therefrom to form a column-like body part to the upper end of which the head part is attached, the body part being of insulating material and having an annular groove formed thereupon near its upper end and having a transverse groove formed across its upper end, the surface of the body adjacent said grooves rounding smoothly from one of said grooves to the other, the head part being of fictile insulating material and being molded about the upper end of the body and into said grooves, so as to fix said body rigidly and inseparably in said head, and the body being adapted to serve as an attaching means.

In testimony whereof I affix my signature in the presence of two witnesses.

LOUIS STEINBERGER. Witnesses: I

NATHALIE THouPsoN, LEO EISENBERG.

copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. O. 

